1. Field of the Invention
This invention generally relates to telephony and, more particularly, to testing of telephone lines for electrical faults.
2. Description of the Related Art
Telephone customers sometimes experience static on their telephone line. Static in a may be caused by corrosion, condensation, or even a break in the telephone line. Static may also be caused by a loose connection between the telephone line and a telephone. Whatever the causes of static, nearly sixty percent (60%) of customer complaints in some areas are due to static in the telephone lines.
Resolving customer complaints of static can be frustrating for telephone technicians. Ambient temperatures, for example, can mask a problem with a customer's telephone line. Sometimes the copper core of a telephone line is only partially cut, creating a “high resistance open” condition. That is, there is a connection at the cut, but the connection is dependent upon the ambient temperature. As the telephone line heats up during the day, the copper core expands and maintains a good connection. When night falls, the copper core cools, shrinks, and causes static on the telephone line. When the technician tests the telephone line during the day, the expanded copper core passes a good dial tone and the technician finds no trouble. The customer, however, still experiences static at night, so another technician is dispatched to repair the same complaint.
This complaint process continues until one or more later technicians suspect a high resistance open condition. Because the telephone line heats and expands during the day, an experienced technician will spray the telephone line with water from a hose. The water eventually cools the telephone line, causing the copper core to shrink. When the technician now tests the telephone line, the partially cut copper core is revealed as a high resistance on the telephone line, indicating an open condition. Although the technician has finally discovered the problem, two hours or more have been spent before the technician even begins a repair.
There is, accordingly, a need in the art for improved testing of telephone lines, a need for determining the causes of static in a telephone line, a need for quickly determining whether a high resistance open condition exists on a telephone line, and a need for improved testing of telephone lines that reduces labor times.